Both primary and metastatic liver cancer is common in the US, and worldwide. The standard treatment for liver cancer is liver resection, where part of the liver containing the tumor is surgically removed. This operation is associated with considerable blood loss, typically between 0.6 - 1 L. Blood loss is adversely associated with patient morbidity and survival, particularly when blood transfusions are required. We have developed a device that allows coagulation of a plane of liver tissue within 3 minutes, including major vessels. The device consists of a linear array of electrodes, to which radiofrequency (RF) energy is applied in bipolar fashion between neighboring electrodes. With our laboratory prototype we were able to coagulate a tissue slice in vivo in porcine liver, including all vessels (up to 4.3 mm in diameter), and subsequently resect along the coagulated slice with negligible bleeding. This device has the potential of reducing blood loss during liver resection surgery to a minimum, with likely increase in patient survival and lowered complication rates. In this proposal we plan use our current laboratory prototype to investigate three different electrode sizes. We will determine the ideal electrode configuration in terms of required performance while limiting tissue trauma due to electrode insertion. We will then show feasibility of our prototype in an animal survival study, where we perform liver resection with our device in five animals. The animals will be monitored for four days after surgery, and any post-operative internal bleeding will be determined. [unreadable] [unreadable] [unreadable]